<!DOCTYPE html>
<html>
<body style="background:white">
<style>
div {
  position: absolute;
  width: 100px;
  height: 100px;
  border-radius: 30px;
  overflow: hidden;
}

span {
  position: absolute;
  top: 0;
  left: 0;
  width: 100%;
  height: 100%;
  background: black;
  transform: scale(2);
}
</style>
<div><span></span></div>
</body>
</html>
